Questions of process are made valid when it becomes clear there may be a flaw in the process which was applied. Asking them if they compiled the code is warranted, is it not?

"This code has more warnings than we accept under our process; please remedy." You aren't telling onlookers that they will be lit on fire for the temerity to contribute, you aren't causing anyone to lose face and you aren't hurting anyone. No aspersions, no chilling effects, and a positive path forward. Done and done. Everyone wins. To do otherwise is inhumane.

That fails to address the possibility that their process is broken, and so achieves the possibility of inducing technical debt when these issues will inevitably arise again.

Fixing process can be as important as fixing code.

There have been a lot of electrons perturbed dancing around that that's what we're talking about, yes?

I'm not pro-insult, not by any means.